Powder actuated tool



Jan. 29, 1963 R. wr KissANE POWDER ACTUATED TOOL 3 Sheets-Sheet 1 Filed Jan. 18, 1961 Jan. 29, 1963 R. W. KISSANE POWDER ACTUATED TOOL 3 Sheets-Sheet 2 Filed Jan. 18, 1961 Jan. 29, 1963 R. W. KISSANE POWDER ACTUATED TOOL Filed Jan. 18, 1961 s sneek-sheet s i247 /20 27 /37 '2f/4M y M, La@

/ViTfRA/fysl United States Patent Oiitce 3,@7592 Patented dan. 29, i953 This invention relates generally to fastener driving tools and more particularly to a tool of the type for driving powder actuated fasteners.

The principal object of the present invention is to provide an improved powder actuated fastener driving tool of structural simplicity, economically manufactured and eiiiciently, safely and easily operated.

Other objects and advantages of this invention will become apparent hereinafter.

ated a barrel assembly housed in a side opening housing and slidable in the housing between inoperative and operative positions, firing pin means rendered operative barrel is in operative position only, shield means,

and abarrel spring having an operative connection with each of said barrel assembly, shield, safety and ejector means.

The invention also consists in the parts and in the arrangements and combinations of parts described and claimed. In the accompanying drawings which form a part of this specification and wherein like numerals identify like parts wherever they occur:

FlG. 1 is a vertical cross-sectional view taken through the length of a tool embodying the invention and showing the parts in inoperative position,

FIG. 2 is a view similar to FIG. 1, but showing the parts of the tool in ready-to-re position,

G. 3 is a cross-sectional View taken substantially along line 3-3 of FIG. l,

FIG. 4 is a cross-sectional view taken substantially along line 4 4- of FIG. l, and showing the breech in an open loading position in broken lines,

FIG. 5 is a horizontal view, partly substantially along line 5 5 of F G. l

FIG. 6 is a cross-sectional view taken substantially along line 6-6 of FIG. 5,

FIG. 7 is an elevational view, partly in cross-section, showing the ejector device of the tool,

8 is a fragmentary sectional view of the tool showing a barrel extension device, and

FIG. 9 is a vertical cross-sectional view taken along line 9 9 of FIG. S.

Referring now to the drawings, the tool tti shown for in section, taken housing member 14 and front breech breech member, respectively. An annular shoulder 31 is formed between the barrel 29 and breech portion 30 0 limits the relative forward position of for abutment against the shoulder 25 to position the barrel assembly as will appear hereinafter. 32 forming a powder charge and fastener receiving chamber 33 in its and has a plurality of ports adjacent its muzzle end for the .escape of gas therefrom. A barrel extension 35, FIG. 8, is also provided for special placethe front housing lli, and a shield 40 defining a hollow enclosure 4l. The shield ed has an annular flange 42 threaded in the end of the sleeve 3.3, and forming an axial opening 43 through which the muzzle end of the barrel 2-9 extends. A muzzle cap te is threaded on the end of the barrel 29 ment, at 45, for limiting limited contact areas 49 for sliding engagement with the bore 17 of the liner 16 and flats 49 for accommodating dust and like foreign particles. This foreign matter inevitably gets into the tool housing 1 4 and tends to bind permit the use of the barrel extension 35 while having its free end 50 maintaining an operative sliding lit in the muzzle end 39 of the barrel housing 1li.

The rear housing member El has an axial bore 5l with an open breech end 52, and a back breech member 53 forming a portion of the housing has a hinge portion 54- positioned against the breech end 52 and a cylindrical portion 55 received in the bore Si and secured to the housing l1 by fastening means 55. The rear housing member 1.1 and back breech member :'33 together forming a firing pin assembly housing. The cylindrical portion 55 has a bore 57 with a back wall 53 and houses a ring pin assembly 59, the bore 57 being substantially conterminous with the bore 243 of the front breech member 1S. The back wall 58 has a bore 6i? and a counterbore of forming a chamber for a firing pin member o2, the tiring pin having a stepped shank portion 63 forming an annular abutment shoulder 63 and extending through the bore 6d toward the cartridge chamber 33, an annular stop ed being formed on the pin 62 for abutment against the shoulder 67 at the forward end or" the chamber to limit forward movement of the firing pin 62 relative to the chamber. The tiring pin 62 is biased forwardly by a spring 55 in the chamber, and the chamber may include a bore 66 formed in the housing il or the bore di in the back breech housing 55 or both of the bores 66 and el. The forward end of the shank 63 carries the pin element 68 of the iiring pin member 62 adapted for striking coutact with powder cartridges (not shown) in the breech chamber 33.

The tiring pin assembly 59 includes a cylindrical firing pin housing 69 slidably mounted in the back breech bore 57, the cylindrical pin housing 69 is positioned to assure non-rotational movement thereof. "the guide pin also the tiring pin hous- 53, as will become The ring pin housing 69 ing 69 in the back breech member more apparent hereinafter.

with the 'slot70 and guide rvpill Vbreech member-'53. A spring Y[a vside opening breech for loading `the tool 10 is opened.

on' a radius from `rnember 53 is provided with a hook member 97 substantially complementary to the groove wall and preferably "havin g a Vslight frictional tit therewith.

Y, the Vring pinhousing ,annular depression vface 103 of the "radially extending limit surfaces roe and tes;

has 'a tiring pin bore 72 extending in an axial direction therethrough, and a vertical cross bore 73 intersects the iiring pin bore 72 and houses asear 74. VThe searis biased downwardly by a sear spring 75 and has a detentS which extends through an elongated trigger opening 76V in the housing 11. A trigger 77 'is positioned in `-a guard opening and has a lever 78 pivoted, 'at 79, tofthe handle 12, the trigger 77 having an elongated sear contacting surface S arranged in operative position lfor contact with the senr detent 37 at all times. A leaf return spring 8 1 is provided for returning the trigger v7 7 to the positionshown in FGS. l and 2 after firing, and it will b'e noted that a large degree of leverage is provided.

The scar 74 includes a keyhole openingincluding a large lower bore 82 and a small upper bore S3, the bore 82. being adapted to receive the tiring pin shank 63 therethrough when the tool is tired and the upper bore $3 being adapted to retain the pin element 68 when vthetlring `pin 62 and tiring pin housing 691ar'e in theirfextended inoperative positions, FlG. l, and the surface 'ofthe'sea'r 74 around the bore 8? engaging vtheabutment'shoulder This'lost-motion movement of the tiring pin 62 relative to the housing '61? land'sea'r parts of the tool 'ltlfr'om an inoperative 'ro-are position as in F1o. 2 win be dennen more fully 63' in a lost-motion connectiony during cooking ofthe tool, HG. 2.

i 77 vduring Aactuation for the -position as in FIG. l 'to an 'operative or cocked, readyhereinafter. The detent S7 is elongated in 'an axial ,direction of the 'tool and is positioned in an 'elongated lower islot 4841 in the cylindrical portion 55 of the back breech member to prevent rotation of the Vsear 74 during movement of the tiring pin housing 69 between inoperative and operative positionsso that the keyhole opening 82, 83`t`or the ring pin 62- will be maintained in an axial position. The axial limits ofthe slot 184 also cooperate V71 in limiting forward movement of the tiring pin housing 69 relative to the back 85 is positioned Vin the bore 57 of the back breech 'member 53 between the back wall SS and the firing pin housing 69 to bias the latter toward the breech portion 39 of the barrel assembly 28 when the tool is cocked. Y

As shown in FlGS. l, 4 and 5, the present tool, ,1b has the chamber 33, the front and back breech members 18 and 53 having mating faces 90 and 91 and being hinged on pin 92 for relative pivotal movement. 'Friction locking means 93'are V4provi'dedfor maintaining the breech members 13 land 53 in closed position, the locking means comprising'spring loaded balls 94 mounted in the hinge portion 54 or the back breech member 53 and seated in mating depressions 95 formed in the face 91 ofthe Vhinge portion 19 of the front breech member 18. The hinge pin 92 is located in a lower projecting portion of the front and back breech member hinge portions 19 and 54 so that the breech end or the barrelv assembly 28 will be fully exposed when Diametrallyopposite to the hinge pin 92, the hinge Vportions are provided with intertting means' to prevent'axial separation of the breech members 18 and 53 during ring of the tool. The front breech member has Van arcuate groove 96 milled substantially the hinge pin 92 and the back breech The breech portion 36 of the barrel assembly 2S and 69 of the firing pin assemblyl'also have an intertting relationship. The breech portion 30 includes a neck til) and Vhead 1131 through which the Cartridge and fastening means chamber 33 extends, lan 102 being formed at the lrearward head 191 for seating the rims of powder cartridges (not shown). The neck Zitltll is vreduced in size relative to the breech rportion '3u and head 101 to form as will 'be 75 upper block V133v moving theblocks apart t V is being closed after loading the chamber 33.

Yejector lug of the head 161 and being substantially iiush therewith.

chamber 33 toward the elliptical portion inside of Y the spring "An elongated opening 12S, -of the housing 14' and liner fand'sliield device wardiy extending sides freely slidable.

' of the plate 132 is biased toward i by a-leaf spring lis vsecured to the cent'erjof vthe latch plate 132 and a similar neueres Vis described. However, a portion of the neck and head project radially outwardly, as at 106, in an elliptical-like pattern, FIG. 4. The firing pin housing 69 has an end face 168 in opposed relation with the surface 104 of the breech portion 3G, and this housing 69 is machined to lform a yoke 169 to receive the neck 160 of the barrel assembly 2S and to form a recess 110 to receive the head 101. The recess has opposed surfaces 111 and 112 and the firing pin bore 72 opens into the recess through the surface 112. As shown in FIGS. 4 and 5, the yoke 109 and recess 110 have a side opening, at 113, for relative pivotal action ofthe housing members to expose the barrel assembly 28 for loading the chamber 33. 1t will be noted that the axial distance of the neck 10i) Vbetween the opposed surfaces 1134 and 165 is the same Aas the axial distance of the recess 11b between the surfaces 111 and 112, and that the yoke 169 and head 101 are adapted for relative axial movement. Still referring to FlGS. 'fandS, the hinge portion 54 ofthe back breech member v5 3 has a lside open section 114 to permit clearance of 'the neck 100 and head 101 of the barrel assembly 2S, and the tiring pin housing 69 is beveled, at 115, to prevent jamming the head 191 thereagainst when the tool The breech 'portionSll of the barrel assembly V28 has a longitudinal 'or axially extending slot 116 formedin its side in which Ya guide pin 117 is positioned for providing rectilinear non-rotational'movement of the barrel assembly 23 inthe housings 11 and 14.

Referring now to FlGS. l, 4, 5 and 7, an ejector mechanism 121) is provided for discharging spent cartridge shells from the chamber 33, the ejector 126 including an i 121 positioned in a recess 122 in the face 103 The lug 121 extends radially from the cartridge shell 166 of the head, and has a lip 123 forming a portion of the continuous cartridge rim engaging depression 162. The lug 121 is Ysecuredon arod 124 slidably mounted in an axially extending bore 125 through the ellipse portion 166 o the head 1tl1and neck 10b and'thro'ugh'the breech portion 3i) of the barrel assembly 28. The rod124has its other end secured to' a collar 126 circumscribing the barrel 29 47. The collar 126 includes spaced lugs 127 which receive and vseat 'a turn ot the spring 47 thereby biasing the' collar in a forward direction (toward the muzzle end of the tool 1li) to normally` maintain the lug 121 in a retracted position seated in the recess 122. FIG. 7, is formed in the wall 16, and a handle 129V extends outwardlyof the housing and is threaded in on'e lug 127. The safety mechanism@ against which one end of the barrel spring 47 is seated, is provided to assure vthat the tool 10 -will not be operative in the levent the spring 47 37 are removed. As shown in FIGS. l, 2, "5 :and '6, the Ysafety mechanism 4S includes a yoke member or latch plate 132 positioned above an annular groove 133 inthe barrel 29,1F1G. l, and having down- 134 with arcuate slots 135 through which bolts 136 extend and are secured to the'cylindrical portionv 21 of the front breech member 14. Spacers are provided to maintain the bolts 136 ina loose litting relationship in`the`slots wherebythe latch plate l132 is The sides 134 o the plate clear the barrel'gro'ove 133 and barrel 29 and vthe lower margin the barrel groove 133 137. An upper beveled guide'block 138 rsecured to the end of the cylindrical portion 2 1 of the front breech member'diarnetrally opposite to the upper block 138. Whenrthe spring 47 is assembled in the barrel bore .17 under compression, its

endY seats` against the xed'lo'wer block 139 and movable raise the latch housing d plate 1132; against the biasing action of the leaf spring 137 and clear the barrel 29 for axial movement.

Referring now to FIGS. l, 8 and 9, it will be seen that the barrel extension 35 may be threaded on the muzzle end of the barrel 29 in lace of the muzzle cap ed and the muzzle cap is then threaded on the outer end ldd of the barrel extension 35 to retain the guard or shield device 37 thereon. The length of the sleeve 3S is predetermined so that the free end t? is positioned within the bore ll/ of the housing ld adjacent to the muzzle end 39 thereof. A longer barrel spring el? must be substituted to provide the compressive force necessary to maintain a normally expanded or inoperative condition of the tool parts. The barrel extension 35 is utilized in placing fasteners in recessed openings and the like Where the shield would be moved relative to the barrel, and it is necessary that extra barrel length be provided to assure movement of the barrel and tiring pin assemblies 23 and di? to ready-to-rire position, as will be described.

inasmuch as the tool can be conditioned for tiring when the barrel means 3S extend beyond the shield dll a substantial distance under the foregoing circumstances, a safety device 145 is provided so that the operator cannot accidentally discharge the tool and must manually release the shield for relative recessing movement into the housing bore i7.

The safety device lf3-5 comprise member ido received in a bore ld and counterbore E48, the counterbore intersecting the housing bore i7 and airr7 its outer end closed by a plug M9. The member includes a rod portion slidable in the bore .lll-'7 an' extending outwardly or the housing le, and an enrged head or stop portion slidable in the counterbore between a retracted, inoperative position in the 14S and a normally extended position in which the stop lSli projects into the barrel bore l'l'. Spring means E52 are provided for biasing the stop portion lS of the member T1455 toward its normally extended position in the bore lu normal operation oi the tool 1i) (when no extension 3S is needed) the shield sleeve extends past the member ide and acts against the shoulder i533 between the rod and stop portions l5@- and l overcoming the force of the spring 152 to maintain the stop portion in retracted inoperative position in the counterbore -t. H wever, when the barrel extension 35' is attached to the barrel portion 29, the shield d@ is positioned outwardly of the muzzle end 39 of the with the free end Sti of the sleeve 3b? adiacent to the housing muzzle and outwardly of the safety device lele'. Accordingly, the member 2de is unrestrained and is moved laterally to its extended operative position in the bore i7 by the spring 152 thereby forming a positive stop in the bore 17 with respect to relative sliding movement or" the sleeve 3S therein. ln order to condition the tool for operation the member lo is moved laterally by manual pressure on the tree end ot the rod 'll.

Referring aga'n to l it will be seen that in the inoperative posi on of the tool l@ the barrel spring 7 exerts a force on trie muzzle end of the barrel assembly 2S (acting against the shield sleeve d2 and muzzle cap d4) to maintain the barrel assembly in an expanded position relative to the front housing i4) and front br ech block i3. The shoulder of the barrel assembly 2S is in abutment with the shoulder 25 of the front breech bloei: to position the rear surface ldd of the enlarged breech portion Si? forwardly of the mating faces E99 and 91 of the front and rear breech members l@ and 53, respectively. The spring 8S of the tiring pin assembly 59 positions the assembly in an inoperative forward position with the front end fece i458 of the yoke member lili@- spaced apart a predetermined distance from the surface idf:- of the barrel breech portion 39 and rearwardly of the mating surfaces 9d and 9i of the breech members i8 and 53. rl`he forward position of the firing pin assema laterally moveable bly 59 is determined by the guide pin 7l forming an v before abutment with the end of the slot 743 and the detent d'7 of the Sear 74 abutting the forward end of the slot $4. The clearance between the surfaces 164 and T108 is provided so that the neck lll@ ot the barrel and the yoke itl@ of the tiring pin assembly are aligned relative to the hinge faces 9d and @l of the housing members for opening and closing the tool for loading purposes.

iroper alignment or positioning of the neck and head Miti, lill relative to yoke recess 109, llo is also assured by the bevel surface MS of the firing pin assembly 59, FIG. 5. This surface it also assures that a cartridge inserted into the cartridge chamber 53 is properly seated with its rim in the annular depression lil?. and not projecting out of the chamber at an angle. in other words, a wiping or camming action is provided between the shell and breech faces when the tool is closed to slide the cartridge shell into place.

Referring to FEGS. 4, 5. and 7, the ejector mechanism l2@ is adapted to be moved between a normally retracted position in which the ejector lug 121 is ilush with the surface iil of the barrel head lill. and an extended or operative position in which the lug 121 is moved axially rearwardly so that the lip 23 will eject a spent sh ll from the annular depression MP2. The barrel spring d'7 exerts a return force on the collar 126 of the ejector mechanism against which a manual ejection force is applied and which return force maintains the normally inoperative position of the lug lZl.

The tiring pin assembly S9 includes the scar 7d having an operative position relative to the trigger surface d@ at all times except when the tool has been discharged and the parts of the tool are returned to inoperative positions for re-loading. inasmuch as the trigger has a large leverage because of the lever '7d and remote pivot point 79 thereof, a stronger sear spring 7S may be provided to prevent accidental movement ot the scar 7d while still providing a relatively light trigger action.

The travel distance of the tiring pin o2 from its readyto-ire or cocked position is predetermined relative to the length of the bore 72 of the tiring pin assembly 59 between the head or pin element 62 and the cartridge rim position in the recess id21, and the required indent of the tiring pin to discharge a cartridge shell is precise. The force of the firing pin spring 65 is also predetermined, and the relative movement of the housings li and le.

elative to the barrel and ring pin assemblies 23 and 59 to provide a substantially full compression of the springs d? and d5 is required position the tiring pin assembly in substantially lrm abutment with the end wall 58 and barrel assern ly 2S so that tie tiring pin will be cocked and operative to discharge a cartridge when the trigger 77 is actuated. An insert plug tft-l is provided in a recess M2 in the muzzle end 339 of the front housing 14 to function as an abutment for the shield member 4o and predetermine the axial movement of the shield and barrel assembly 2S relative to the housing ld. Accordingly, the relative axial movement of the barrel assembly and tiring pin assembly toward cocked position in the tool housings il and le can be precisely set in a simple manner.

lt will be noted that a manually applied pressure pushing the tool housings l1 and ld toward a work surface fastener is to be placed will press the ready-to-tire poston in which the tiring pin is in abutment with the end housing 55. During this movement toward ready-to-ire position a lost-motion connection is provided between the scar 7d and tiring pin abutment 53', the scar sliding agravada? upwardly in its bore '73 to receive the forward reduced shank portion whereby substantial movement of the parte toward ready-to-fire postion must occur before the tiring pin is engaged and moved to load the firing pin spring 65. it will also be noted that the discharge or forward travel distance of the firing pin before the stop 64 contacts the shoulder 67 of the chamber 61 is preselected so that the tilting pin head 1S will precisely contact a cartridge in the chamber 33. However, in the event the firing pin housing 69 is not substantially fully moved to ready-to-i'lre position to cock the firing pin 62 the distance between the stop member 64 and the shoulder 67 will be shortened whereas the travel distance between the tiring pin head 68 and the cartridge is lined. Accordingly, unless the barrel and firing pin assemblies are moved to a fully retracted postion, the ring pin stop member 6d will prevent discharge of the cartridge even if the trigger 77 is moved to actuate the sear 74, in which case the tiring pin shank 63 is released into the sear bore 83 and will require the tool to be returned to inoperative position in order that the firing pin 62 may be engaged by the sear and conditioned for operation. It will be readily apparent that if the tool 1d is tilted 'at an angle to the surface 1.42, the shield will not form a so that dust and particles may escape around the shield when the tool is fired and create a hazardous work condition. It is also apparent that even though the shield 40 may be moved relative to the housing 14 to compress the spring 47, the barrel assembly 2S will be biased to ward an extended position by the tiring Vpin assembly S9 and its relatively weaker spring 85 so that movement of the barrel and tiring pin assemblies toward cocked position is independent of the movement of the shield and requires that the muzzle cap 44 be contacted and moved in concert with the shield for operation of the tool. Therefore, at an angular postion the muzzle cap 44 will contact the work surface 143 after partial relative movement of the shield 4b has taken place whereby movement of the vtool parts to fully operative position with the ring pin housing 69 in abutment with the end wall 58 will not occur if the angle of the shield is above a predetermined maximum, such as 5 to 7.

The other safety features comprise the safety mechanism 4S and the safety device 14S. The mechanism 48 is Vmounted in the housing bore 17 on the Vfront face of the front breech member 18 for radial movement therein. The leafspring 137 biases the latch plate 132 inwardly toward an abutment forming position in the groove 133 of the barrel 32 whereby axial movement of the latter will be prevented. However, the barrel spring 47 has one end seated on the canted blocks 13S and 139 to overcome the leaf spring force and normally maintain a retracted position of the latch plate 132. In the event the shield 40 and spring 47 are removed, the safety mechanism will be operative to prevent cooking action ofthe barrel assembly1 28. The safety device 14S is provided to prevent shield movement into the housing '14 when a barrel extension 35 is used, unless a manual .pressure is applied to move the 'stop portion 151'out of the bore 17 whereby the end 50 of the shield sleeve 3S Acan slide past the safety device 145.

From the foregoing .it will be apparent that a simplified, but positive acting and efficient powder tool has been provided. Changes Aand modiiications of the foregoing specification that'will be readily apparent to all skilled in the art are contemplated as within the spirit and scope of the invention, which is limited only by the claims which follow.

What I claim is:

l. 'A powder actuated tool comprising front and rear housing members hinged together forv side opening movement, Va barrel assembly slidablein the housing members between forward inoperative and rearward Voperative positions and' having a breech endv for receiving Va cartridge, ari'ngpin assembly slidable in the rear housing closed chamber 41 with the surface of said sear and said breech member between forward inoperative and rearward operative positions and including a tiring pin and liring pin control means, said tiring pin control means having a lost-motion connection with said barrel assembly for subsequent concert movement therewith to operative position and also having a lost-motion connection with the tiring pin for moving it to a ready-to-fire position in the latter portion of barrel assembly and tiring pin control means movement to operative postion, and means for limiting the travel distance of said tiring pin toward the breech end of said barrel assembly whereby said firing pin will not discharge a cartridge unless said barrel assembly is substantially fully retracted to operative position.

2. The tool according to claim l wherein trigger means are provided in operative postion relative to said tiring pin control means, and said firing pin control means normally slidably engage the tiring pin for guiding the tiring pin in its lost-motion movement relative to said tiring pin control means.

3. The powder actuated tool according to claim l wherein said front and rear housing members have mating faces in sliding contact during side opening movement of said housing members, and the space defining the lostmotion connection between said barrel assembly and firing pin control means extending axially lon each side of said mating faces of said housing members.

4. The powder actuated tool according to claim l wherein said tiring pin control means includes a breech member slidable in said rear housing member and having a tiring pin bore, a cross bore in said breech member, and a sear postioned in said cross bore and having a keyhole opening receiving at least a part of said tiring pin at all times.

5. The powder actuated tool according to claim 4 wherein sear spring means are provided between one end member to normally maintain said sear in an inoperative postion, the other end of said sear projecting out of said rear housing member, and trigger means having a sear contacting surface in position to contact said other end of said sear.

6. The powder actuated tool according to claim 5 wherein said trigger means includes a lever pivoted at a point remote from said sear contacting surface whereby said sear is adapted to be maintained against accidental displacement by relatively strong Sear spring means.

7. In a tool of the type described, a housing including iirst and second members releasably secured together and adapted for relative opening movement, a barrel slidably postioned in said first member, spring means between said barrel and said rst member urging the barrel to a forward postion away from the second member, ejector means positioned within the irst member for sliding movement relative to said barrel and nrst member, said ejector means being movable from ka retracted postion tomuzzle end of said barrel ward said second member for ejecting spent cartridges when said members are in open position, said ejector means having an operative connection with said spring means and being normally maintained in said retracted position thereby. Y

8. ln a tool of the type described, a housing including front and rear members releasably secured together and adapted for opening movement, said front housing member having a front bore and a rear counterbore, a barrel assembly including a breech portion slidably postioned in said rear counterbore and a barrel positioned in said front bore in spaced relation with the bore wall to denne an annular chamber, said barrel having a muzzle end, said breech portion having a cartridge receiving opening including an annular recess for seating the cartridge rim, compression spring means in the front bore between the and front housing member normally maintaining the barrel assembly in a forward postion relative to the front housing member, and ejector means including a lug recessed in the breech portion of said barrel assembly and having a lip forming a portion 10. In a tool of the type described, a housing having a bore, a barrel assembly mounted for sliding movement within said bore and including a muzzle end and a breech end, barrel spring means for normally maintaining said barrel assembly in an expanded position forwardly in said housing bore, safety means mounted relative to said housing, said barrel spring means being positioned between said muzzle end of said barrel and mounted for limited radial movement on said housing at the inner end of said bore between said barrel assembly and the bore wall, an arcuate leaf spring secured to said latch plate and engaged against said bore wall biasing said latch plate radially inwardly toward said barrel assaid latch plate including first camming means having an inclined said latch plate toward an operative position within the groove for preventing axial movement of said barrel assembly toward its operative postion in said housing bore, and said spring means having its other end seated against camming means and exerting a force greater than said leaf spring 13. A powder actuated tool comprising front and rear housing members pivoted for side opening movement, a barrel assembly slidable within and relative to the housing members between a forward inoperative position and a rearward ready-to-iire position, said barrel assembly having a -breech end adapted to receive a assembly unless said barrel assembly and breech block member are substantially fully retracted to ready-to-re position.

References Cited in the tile of this patent UNITED STATES PATENTS Temple Jan. 18, 1921 Walker July 21, 1953 Bossong Apr. 5, 1955 Magnuson Apr. 30, 1957 Temple et al. Nov. 3, 1959 Kopf et al July 19, 1960 FOREIGN PATENTS Great Britain June 19, -1957 Great Britain Mar. 18, 1959 

1. A POWDER ACTUATED TOOL COMPRISING FRONT AND REAR HOUSING MEMBERS HINGED TOGETHER FOR SIDE OPENING MOVEMENT, A BARREL ASSEMBLY SLIDABLE IN THE HOUSING MEMBERS BETWEEN FORWARD INOPERATIVE AND REARWARD OPERATIVE POSITIONS AND HAVING A BREECH END FOR RECEIVING A CARTRIDGE, A FIRING PIN ASSEMBLY SLIDABLE IN THE REAR HOUSING MEMBER BETWEEN FORWARD INOPERATIVE AND REARWARD OPERATIVE POSITIONS AND INCLUDING A FIRING PIN AND FIRING PIN CONTROL MEANS, SAID FIRING PIN CONTROL MEANS HAVING A LOST-MOTION CONNECTION WITH SAID BARREL ASSEMBLY FOR SUBSEQUENT CONCERT MOVEMENT THEREWITH TO OPERATIVE POSITION AND ALSO HAVING A LOST-MOTION CONNECTION WITH THE FIRING PIN FOR MOVING IT TO A READY-TO-FIRE POSITION IN THE LATTER PORTION OF BARREL ASSEMBLY AND FIRING PIN CONTROL MEANS MOVEMENT TO OPERATIVE POSITION, AND MEANS FOR LIMITING THE TRAVEL DISTANCE OF SAID FIRING PIN TOWARD THE BREECH END OF SAID BARREL ASSEMBLY WHEREBY SAID FIRING PIN WILL NOT DISCHARGE A CARTRIDGE UNLESS SAID BARREL ASSEMBLY IS SUBSTANTIALLY FULLY RETRACTED TO OPERATIVE POSITION. 